Great video , by chance do you have anymore video's(or link sources)on this particular section of calculating area of countries, and do you have vids and sources about the entire process of obtaining information(possibly from satellites) to calculate accurate area of a country/ continent.
I don't have any other videos on calculating the area. I would love to be able to make some other videos on these subjects though. Maybe I will be able to get back to it one day.
I really wish I could do this. My software keeps complaining about it not being versioned. It is just a calculation I am not interested in publishing anything at this point. Thank you nevertheless for showing how cool this tool could be.
That is correct. ArcGIS calculates area based on the projection the project is in. It is not "smart" enough to understand how to calculate area independently of how the data happens to be displayed at the current time.
@@trishl9775 UTM is "Universal Transverse Mercator". The Mercator projection is a conformal map projection. So, it is not equal area. I am not sure what state you are in, but most State Plane projections are either based on transverse Mercator-based or Lambert Conformal Conic-based. Neither of those are equal area. But you should check that based on your state, and also what the expected error rate is with area calculations when using is. But, retrojecting the data to an equal area projection before running an area calculation in ArcMap is always recommended.
It was because this is an educational demonstration. Yes, these data did already have an area field in the data. Assuming that the numbers in the data were correct, if ArcGIS is "smart" enough to always calculate area correctly when requested, then the caucluted numbers and the numbers already in the data should be identical. They are not, and so that should to send up red flags about excactly what is going on with the its area calculation algorithims. Plus, most analysits would not accept numbers that came with the data anyway without being able to document how they were produced or being able to replicated those numbers himself or herself. So, that is what we are doing here.
good stuff! that was a GREAT explanation and demo. thanks
Any tool for split WGS UTM zones to calculate them geometry area individual, or you think calculate area in this "equal" is the realistic ressults?
Great video , by chance do you have anymore video's(or link sources)on this particular section of calculating area of countries, and do you have vids and sources about the entire process of obtaining information(possibly from satellites) to calculate accurate area of a country/ continent.
I don't have any other videos on calculating the area. I would love to be able to make some other videos on these subjects though. Maybe I will be able to get back to it one day.
I really wish I could do this. My software keeps complaining about it not being versioned. It is just a calculation I am not interested in publishing anything at this point. Thank you nevertheless for showing how cool this tool could be.
are you saying we should always use an equal area projection when calculating area?
That is correct. ArcGIS calculates area based on the projection the project is in. It is not "smart" enough to understand how to calculate area independently of how the data happens to be displayed at the current time.
@@GeoMindzcom I usually use a State Plane or the UTM projection/coordinate system. Are these considered equal area projections?
@@trishl9775 UTM is "Universal Transverse Mercator". The Mercator projection is a conformal map projection. So, it is not equal area. I am not sure what state you are in, but most State Plane projections are either based on transverse Mercator-based or Lambert Conformal Conic-based. Neither of those are equal area. But you should check that based on your state, and also what the expected error rate is with area calculations when using is. But, retrojecting the data to an equal area projection before running an area calculation in ArcMap is always recommended.
from the beginning, it's n
ot clear why yiou are calculating area when area already exists in the attribute table
It was because this is an educational demonstration. Yes, these data did already have an area field in the data. Assuming that the numbers in the data were correct, if ArcGIS is "smart" enough to always calculate area correctly when requested, then the caucluted numbers and the numbers already in the data should be identical. They are not, and so that should to send up red flags about excactly what is going on with the its area calculation algorithims. Plus, most analysits would not accept numbers that came with the data anyway without being able to document how they were produced or being able to replicated those numbers himself or herself. So, that is what we are doing here.